Microclimatic regulation effects of landscape elements on university campus in a temperate monsoon climate zone: A case study during extreme summer heat

Although temperate monsoon climate regions are traditionally known for their harsh winter climates, the combined effects of rapid urbanization and global climate change have significantly intensified summer urban heat island effects in these areas, making them a neglected yet increasingly severe challenge in high-latitude urban climate adaptation planning. This study takes a typical campus in Shenyang, a temperate monsoon climate region in Northeast China, as the experimental subject. It quantitatively dissects the non-linear statistical associations and regulatory mechanisms of biotic and abiotic landscape elements and their spatial configurations on microclimate parameters and human thermal comfort (Physiologically Equivalent Temperature, PET) by combining microclimate field observations with validated ENVI-met numerical simulations. Field measurement results show that the vertical structural characteristics of vegetation dominate cooling efficiency: evergreen trees and shrubs, with their dense radiation-blocking structures, exhibit optimal regulatory potential, with mean Physiological Equivalent Temperature (ΔPET) values reaching 10.6°C and 10.4°C, respectively, significantly outperforming deciduous trees (8.1°C). In contrast, abiotic elements play an auxiliary role, with dynamic water bodies and enclosed pavilions providing PET improvement values of 3.1°C and 2.9°C, respectively, while paving materials have limited direct regulatory capacity (< 2.0°C). Simulation optimization further reveals a significant “blue-green synergy” effect: the composite configuration of high-canopy evergreen trees and large-area dynamic water bodies forms the optimal spatial solution, reducing daily average PET to 48.7°C, a decrease of 7.3°C compared to the vegetation-free baseline scenario. Addressing the unique “humid-heat” challenge that distinguishes temperate monsoon climates from arid or semi-arid regions where summer thermal stress is often attributed solely to high temperatures, this study goes beyond merely documenting cooling effects to elucidate the “structural-thermal decoupling” mechanism in temperate monsoon climates. It challenges the conventional “deciduous-first” design paradigm by quantifying the superior radiative-blocking efficiency of evergreen species during extreme heatwaves, providing a physically-grounded framework for campus microclimate resilience.